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对羟肟酸类捕收剂的浮选机理、羟胺法合成羟肟酸的原理和方法进行了介绍和分类;在考察醇、醇/水、水溶液和乳液4种肟化反应介质下工艺特点的同时,详细阐述了羟胺法改进工艺的研究进展;针对羟胺法的工艺特点和羟肟酸分子构效关系,提出了羟胺法合成羟肟酸的发展趋势。 相似文献
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羟胺(盐)是一种重要的化工原料。传统的羟胺制备方法,如拉西法、催化还原(HPO)法等,存在污染环境、工艺流程冗杂、设备腐蚀严重、原料原子利用率低等不足。基于绿色化学理念和羟胺合成的研究现状,本文以酮肟水解制备羟胺反应为重点,从水解反应的原料、催化剂、反应产物及其分离方式等角度,阐述了酮肟水解法制备羟胺产品的研究进展;并同时针对酮肟水解反应提出了质子化酮肟的反应机理,讨论了反应蒸馏(精馏、萃取)-耦合、聚二甲基硅氧烷薄(PDMS)膜原位分离法等新型反应、分离技术在酮肟水解中的最新应用。在此基础上,指出借助反应萃取-耦合等新型反应、分离技术,开发温和条件下清洁高效的催化酮肟水解一步合成羟胺及其盐的工艺过程,或将成为今后研究的热点。 相似文献
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丙酮肟及固体羟胺的合成 总被引:5,自引:0,他引:5
研究了丙酮肟和固体硫酸羟胺的合成,对生成丙酮肟反应的影响因素进行了探讨.在所得的丙酮肟中,滴加浓硫酸或浓盐酸,可以分别得到固体的硫酸羟胺或盐酸羟胺. 相似文献
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综述了近年来国内外羟胺法合成异羟肟酸的几种方法,介绍了其合成原理。重点介绍了常规的羧酸酯、酰氯和羧酸与羟胺反应法的研究进展,并涉及了非常规微波法和连续流动反应器法,这两种方法不仅用时少,而且转化率高,具有重要的研究意义。另外,综述了异羟肟酸在金属矿物浮选、金属离子萃取和医药领域的应用,异羟肟酸应用广泛,并且在各方面应用中均具有优良的性能,研究开发异羟肟酸具有较好的发展前景。 相似文献
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研究了一系列取代苯甲醛、杂环醛和脂肪醛与盐酸羟胺在酸催化剂存在条件下合成相应腈的新方法,考察了原料配比、催化剂种类、反应时间、溶剂用量及温度等因素对反应的影响。结果表明,合成目标物的优化工艺条件为:n(醛)∶n(盐酸羟胺)=1.0∶1.4,催化剂为硫酸氢钠,相转移催化剂为四丁基溴化铵,135℃反应47 h,收率达68.6%7 h,收率达68.6%97.9%。具有生产成本低、反应条件温和、易于工业化生产的优点。 相似文献
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硫酸羟胺作为一种重要的中间体,在医药、农药生产中有着广泛的应用,文章介绍了硫酸羟胺的三种合成方法,着重介绍了硫酸羟胺在柠檬腈、N-羟基邻苯二甲酰亚胺、杀线威合成中的应用情况,并就国内硫酸羟胺的产业化提出了一些建议。 相似文献
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2,5-Dicyanofuran (DCF) is an important biomass-derived platform compound primarily used to prepare bio-based adiponitrile, which is the key precursor for the synthesis of nylon 66 and 1,6-hexanediisocyanate (HDI). In this study, one-pot, green and safe synthesis of DCF from 2,5-diformylfuran (DFF) and hydroxylamine ionic liquid salts was proposed. Eco-friendly hydroxylamine ionic liquid salts were used as the nitrogen source. Ionic liquid exhibited three-fold function of cosolvent, catalysis and phase separation. The conversion of DFF and yield of DCF reached 100% under the following optimum reaction conditions: temperature of 120 ℃ for 70 min, volume ratio of paraxylene: [HSO3-b-Py]·HSO4 of 2:1, and molar ratio of DFF:(NH2OH)2·[HSO3-b-Py]·HSO4 of 1:1.5. The reaction mechanism for the synthesis of DCF was proposed, and the kinetic model was established. The reaction order with respect to DFF and intermediate product 2,5-diformylfuran dioxime (DFFD) was 1.06 and 0.16, and the reaction activation energy was 64.07 kJ·mol-1 and 59.37 kJ·mol-1 respectively. After the reaction, the ionic liquid was easy to separate, recover and recycle. 相似文献
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由克拉霉素的前体6-O-甲基-2′,4″-二(三甲基硅)-红霉素A9-(1-异丙氧基环己基)肟(Ⅰ)出发,常温下以φ(HC l)=10%的盐酸催化水解得3-羟基-6-O-甲基红霉素A9肟(Ⅱ);然后一锅煮进行化合物Ⅱ的2′-羟基乙酰化、3-羟基氧化,得2′-乙酰基-3-氧代-6-O-甲基红霉素A9-(O-乙酰基)肟(Ⅳ);最后脱乙酰基、还原9-肟基再次应用一锅煮法合成,得到目的化合物3-氧代-6-O-甲基红霉素(Ⅵ),总收率为57.0%,经HPLC测定w(Ⅵ)=98.5%。通过1HNMR1、3CNMR和MS,表征了各中间体及目标化合物的结构。 相似文献
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光学纯β-氨基酸是合成拟多肽和β-内酰胺类抗生素等药物的重要中间体,其制备方法通常涉及多步反应,原料昂贵,操作复杂且产率较低。以醛、丙二酸和铵盐为原料,采用“一锅法”合成了5种β-氨基酸消旋体。应用手性配体交换色谱对所合成的氨基酸消旋体进行拆分,获得了光学纯β-氨基酸对映体。结果表明基于“一锅法”合成β-氨基酸消旋体和手性配体交换色谱分离对映体的制备方法具有操作简便,成本低廉,产率较高的特点,适合用于药物高通量筛选不同结构β-氨基酸对映体的快速制备。 相似文献
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Kung R. Chang Hwei W. Chen Chi C. Wan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1984,34(5):237-242
Palladium dispersed on active carbon (Pd/C) is used as a catalyst in the synthesis of hydroxylamine. Alkaline precipitation was used to prepare the catalyst. It was found that the controlling factor was the size of palladium crystal, which in turn was chiefly determined by the PdCl42-/Pd(OH)2 conversion stage. The sintering and crystal growth of Pd was the main reason for the decay of the catalyst. The sintering mechanism was found to follow the Ostwald ripening model. 相似文献
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A novel demulsifier (noted as PSADP) having high molecular weight and branch structure was prepared via one-pot synthesis by using two PEO-PPO demulsifiers (SP-1 and DMEA-1), acrylic acid (AA), and pentaerythritol tetraacrylate (PET4A) as materials. The demulsification experiments showed that PSADP can achieve high water removal and clear separated water at the same time. Optimal preparation condition of PSADP was elected by orthogonal test. In addition, the study of partition coefficient and interfacial dilational moduli showed that the best PSADP had best capacity to displace the natural active agents and destroy the interface. 相似文献
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以丙醛为原料,氯铬酸吡啶(PCC)为氧化剂,乙酸乙酯为溶剂,通过一锅法,在常温常压下合成得到草莓酸,总收率为85.3%。所得产品用IR、1 H NMR等方法进行表征。 相似文献
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Wansheng Huang Prof. Shengtang Huang Prof. Zhoutong Sun Prof. Wuyuan Zhang Dr. Zhigang Zeng Bo Yuan 《Chembiochem : a European journal of chemical biology》2023,24(1):e202200610
Halogenated biaryls are vital structural skeletons in bioactive products. In this study, an effective chemoenzymatic halogenation by vanadium-dependent chloroperoxidase from Camponotus inaequalis (CiVCPO) enabled the transformation of freely rotating biaryl bonds to sterically hindered axis. The yields were up to 84 % for the tribrominated biaryl products and up to 65 % when isolated. Furthermore, a one-pot, two-step chemoenzymatic strategy by incorporating transition metal catalyzed Suzuki coupling and the chemoenzymatic halogenation in aqueous phase were described. This strategy demonstrates a simplified one-pot reaction sequence with organometallic and biocatalytic procedures under economical and environmentally beneficial conditions that may inspire further research on synthesis of sterically hindered biaryls. 相似文献
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